With multiple best-selling books under the belt, Kyung-sook Shin has rock star status in her native South Korea. Now the 48-year-old author is ready to enter the international market with her latest book, “Please Look After Mom” (Knopf, $24.95). The touching novel — about a family that doesn’t appreciate their mother until after she has mysteriously disappeared — sold more than a million copies in Korea. It has since been released in more than 20 countries and debuted May 1 at number 14 on the New York Times Best Sellers list.